The present invention relates to motor vehicle window regulators of the general type disclosed in U.S. Pat. Nos. 3,897,654, 5,809,695, 5,848,496 and 5,960,588. Such regulators commonly use one or two guide tracks each of which supports a cable operated window panel lifting device. For example, the regulators disclosed in the above ""695, and ""496 and ""588 patents use a pair of guide tracks, and the regulator disclosed in the ""654 patent uses a single guide track in the form of a split guide tube enclosing a flexible cable in the form of helically wound wire on a lubricating core material. A formed sheet metal bracket is attached to the lower end portion of the cable and is connected to the lower edge portion of the window panel, for example, by a bonded lifting bar as disclosed in the ""654 patent. The cable usually moves longitudinally within the guide tube by a helical pinion or gear which may be connected to a hand crank or a power operated drive motor and gear reducer unit.
The window panel lifting member of the window regulator is connected to the lower edge portion of the window panel by different methods and devices. For example, a U-shaped bar may be bonded or cemented to the lower edge portion of a glass window panel or U-shaped gripping brackets may be clamped to the lower edge portion of the window panel, for example, as shown in the above ""695, ""496, and the ""588 patents. The window panel may also be connected by a U-shaped lifting bracket with a threaded fastener which extends through a hole within the window panel, for example, as disclosed in U.S. Pat. No. 5,363,595.
It is desirable to eliminate the requirement of forming holes in the glass window panel for attaching the lifting member of the regulator and thereby avoid the cost of forming the holes and possible damage to the window panel. It is also desirable for the connection of the regulator lift member to provide for an adjustable and positive grip of the window panel while also being compact and light weight in addition to being economical in construction and providing for gripping glass window panels with variations in thickness. As apparent, none of the above-mentioned patents provide a window panel lift connection which provides all of these desirable features.
The present invention is directed to a window regulator which incorporates an improved device or unit which connects or clamps the lift member of the window regulator to a window panel and which provides all of the desirable features mentioned above. In accordance with one embodiment of the invention, a clamp unit includes a C-shaped clamp body formed from an aluminum extrusion, and the clamp body defines a recess which receives a U-shaped resilient gasket having upper edge portions confined within corresponding slots within the clamp body. The gasket adjustably receives a lower edge portion of the window panel, and a rigid pressure block is also confined within the clamp body between one leg of the gasket and the inner end of a clamping screw threaded through the clamp body. The clamping screw also extends through a hole within a wing portion of a sheet metal lifting bracket of the regulator so that when the screw is tightened, the window panel is gripped with substantial and uniform pressure and is connected to the regulator bracket.
Other features and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.